US money calendar: every deadline that matters
Estimated tax installments, HSA and FSA cut-offs, Marketplace enrollment, I bond announcements and the dates the next year’s limits are set — from today to the end of 2027, with the days remaining.
Figures as of · day counts from , refreshed in your browser · 33 events
The year rule · January 2026 – February 2027
| Date | Section | Event | Certainty |
|---|---|---|---|
| Wednesday, April 15, 2026 | Estimated taxes | Estimated tax — first installment for 2026 | fixed |
| Monday, June 15, 2026 | Estimated taxes | Estimated tax — second installment for 2026 | fixed |
| Tuesday, September 15, 2026 | Estimated taxes | Estimated tax — third installment for 2026 | fixed |
| Thursday, October 1, 2026 | FSA | IRS annual inflation adjustments, including the 2027 health FSA limits — expected | expected |
| Thursday, October 1, 2026 | Social Security | SSA cost-of-living adjustment and the 2027 earnings-test limits — expected | expected |
| Sunday, November 1, 2026 | Health insurance | Marketplace open enrollment opens for 2027 coverage | fixed |
| Sunday, November 1, 2026 | I bonds | New I bond rates take effect (November 2026 – April 2027) | scheduled |
| Tuesday, December 1, 2026 | HSA | HSA last-month rule test date for 2026 | fixed |
| Tuesday, December 15, 2026 | Health insurance | Last day to enroll for Marketplace coverage starting January 1, 2027 | fixed |
| Thursday, December 31, 2026 | FSA | Health FSA plan year ends — spend-by date for most calendar-year plans | plan-specific |
| Friday, January 1, 2027 | Health insurance | HHS poverty guidelines for 2027 — expected | expected |
| Friday, January 15, 2027 | Health insurance | Marketplace open enrollment closes for 2027 coverage | fixed |
| Friday, January 15, 2027 | Estimated taxes | Estimated tax — fourth installment for 2026 | fixed |
| Monday, February 1, 2027 | Estimated taxes | File your 2026 return and pay in full — and the January 15 installment is not required | fixed |
Each flag hangs at its date in its section’s colour and links to the full entry in the agenda. A dotted flag through the month band means the date is not published yet. Events after February 2027 are in the agenda.
Agenda · from
- in 8 days Estimated tax — third installment for 2026 applies if you pay estimated tax · source [1] ↗ ESTIMATED TAXES →
- date not yet set October–November 2026 IRS annual inflation adjustments, including the 2027 health FSA limits — expected expected window 2026-10-01 – 2026-11-30 · source [2] ↗
The 2026 figures came in Rev. Proc. 2025-32 on October 9, 2025. Any 2027 health-FSA dollar figure circulating before the IRS revenue procedure is a projection, not an IRS figure. FSA → - date not yet set mid-October 2026 SSA cost-of-living adjustment and the 2027 earnings-test limits — expected expected window 2026-10-01 – 2026-10-31 · source [3] ↗
SSA sets the limits from third-quarter CPI-W and announces in mid-October. No 2027 dollar figure exists until then; anything circulating now is a projection. SOCIAL SECURITY → - in 55 days Marketplace open enrollment opens for 2027 coverage source [4] ↗
A court vacated the shortened November 1 – December 15 window in June 2026; HHS confirmed November 1 – January 15 in early August 2026. State-based exchanges may differ. HEALTH INSURANCE → - in 55 days New I bond rates take effect (November 2026 – April 2027) source [5] ↗
November 1, 2026 is a Sunday. Treasury’s practice has been to post the announcement on the next business day (Monday, November 2) while the new rates still take effect November 1. I BONDS → - in 85 days HSA last-month rule test date for 2026 applies if you were not HDHP-covered all year · source [6] ↗
HDHP coverage on December 1, 2026 (a Tuesday) lets you contribute the full 2026 limit — and starts a testing period through December 31, 2027. HSA → - in 99 days Last day to enroll for Marketplace coverage starting January 1, 2027 source [4] ↗ HEALTH INSURANCE →
- in 115 days Health FSA plan year ends — spend-by date for most calendar-year plans your plan decides · applies if your plan year is the calendar year · source [2] ↗
Your plan document decides. A non-calendar plan year ends on a different date. FSA → - date not yet set January 2027 HHS poverty guidelines for 2027 — expected expected window 2027-01-01 – 2027-01-31 · source [7] ↗
HHS publishes the annual update in the Federal Register in January. The 2026 guidelines were effective January 13, 2026; they are the ones 2027 coverage uses. HEALTH INSURANCE → - in 130 days Marketplace open enrollment closes for 2027 coverage source [4] ↗ HEALTH INSURANCE →
- in 130 days Estimated tax — fourth installment for 2026 applies if you pay estimated tax · source [1] ↗ ESTIMATED TAXES →
- in 147 days File your 2026 return and pay in full — and the January 15 installment is not required applies if you skipped the fourth installment · source [1] ↗
February 1 rather than January 31 because January 31, 2027 is a Sunday. ESTIMATED TAXES → - in 189 days Latest a grace period can run for a December 31, 2026 plan year your plan decides · applies if your plan offers a grace period · source [8] ↗
March 15, 2027 is a Monday. A plan may offer a carryover or a grace period — not both — and may set a shorter period. FSA → - in 205 days A common health FSA claim-submission (run-out) deadline — not a rule your plan decides · applies if your plan sets a 90-day run-out · source [2] ↗
There is no IRS-set run-out period. Ninety days is a convention — often 60 to 90 days. Your plan decides; check your plan document. FSA → - in 220 days Estimated tax — first installment for 2027 applies if you pay estimated tax · source [9] ↗ ESTIMATED TAXES →
- in 220 days Federal income tax return for 2026 due (or file for an extension) source [10] ↗
April 15, 2027 is a Thursday. District of Columbia Emancipation Day falls on Friday April 16, 2027, so it does not push the deadline. ESTIMATED TAXES → - in 220 days Last day to make 2026 HSA contributions source [6] ↗
The unextended filing deadline, whether or not you file an extension. HSA → - date not yet set May 2027 IRS revenue procedure with the 2028 HSA and HDHP limits — expected expected window 2027-05-01 – 2027-05-31 · source [2] ↗
The 2027 limits came in Rev. Proc. 2026-24 on May 29, 2026; the IRS has published them in May for years. No figure exists until it does. HSA → - in 236 days New I bond rates take effect (May – October 2027) source [5] ↗
May 1, 2027 is a Saturday; expect the posting on the next business day. I BONDS → - in 281 days Estimated tax — second installment for 2027 applies if you pay estimated tax · source [9] ↗ ESTIMATED TAXES →
- date not yet set July–August 2027 IRS revenue procedure with the 2028 applicable percentages — expected expected window 2027-07-01 – 2027-08-31 · source [2] ↗
The 2027 table came in Rev. Proc. 2026-26 on July 21, 2026; the 2026 table in Rev. Proc. 2025-25 on July 18, 2025. HEALTH INSURANCE → - in 373 days Estimated tax — third installment for 2027 applies if you pay estimated tax · source [9] ↗ ESTIMATED TAXES →
- date not yet set October–November 2027 IRS annual inflation adjustments, including the 2028 health FSA limits — expected expected window 2027-10-01 – 2027-11-30 · source [2] ↗ FSA →
- date not yet set mid-October 2027 SSA cost-of-living adjustment and the 2028 earnings-test limits — expected expected window 2027-10-01 – 2027-10-31 · source [3] ↗ SOCIAL SECURITY →
- in 403 days Extended federal income tax return for 2026 due applies if you filed an extension · source [10] ↗ ESTIMATED TAXES →
- date not yet set November 1, 2027 Marketplace open enrollment opens for 2028 coverage — expected expected window 2027-11-01 – 2027-11-01 · source [4] ↗
HHS confirms each year’s window; the 2028 dates are not published yet. HEALTH INSURANCE → - in 420 days New I bond rates take effect (November 2027 – April 2028) source [5] ↗ I BONDS →
- in 450 days HSA last-month rule test date for 2027 applies if you were not HDHP-covered all year · source [6] ↗ HSA →
- in 480 days Health FSA plan year ends — spend-by date for most calendar-year plans your plan decides · applies if your plan year is the calendar year · source [2] ↗ FSA →
- in 480 days Testing period ends for a 2026 last-month-rule contribution applies if you used the last-month rule for 2026 · source [6] ↗
Stop being HSA-eligible before this date and the extra contribution becomes income plus a 10 % additional tax. HSA → - in 498 days Estimated tax — fourth installment for 2027 applies if you pay estimated tax · source [9] ↗
January 15, 2028 is a Saturday and Monday January 17 is Martin Luther King Jr. Day, so the installment is due Tuesday January 18, 2028. ESTIMATED TAXES →
Earlier this year — 2 dates that have passed
Add these dates to your calendar
All-day entries with a reminder seven days before, at 09:00 in your own timezone. Only events with a real published date are included — nothing expected, nothing set by your employer’s plan.
All 21 dates (.ics) Health insurance (3)HSA (4)I bonds (3)Estimated taxes (11)
No file for FSA or Social Security. Every FSA and Social Security event on this page is either an announcement whose date has not been published or a date your own plan document sets — there is nothing honest to put in a calendar file. The FSA tool builds a single-event file from your plan’s own dates instead.
Questions
Which dates on this page can move?
None of the dated ones. A federal deadline that falls on a weekend or a legal holiday is already shifted here — the fourth 2027 installment is Tuesday January 18, 2028 because January 15 is a Saturday and the Monday is Martin Luther King Jr. Day. The events marked as not yet set are announcements whose date nobody has published.
Why do some events have no date at all?
Because the agency has not set one. The Social Security cost-of-living announcement is expected mid-October 2026 and the IRS annual inflation adjustments are expected in October or November, but neither has a published date, so this page shows the window and the words rather than inventing a day.
What is in the calendar file I can download?
Every event that has a real, published date and is not set by your own plan: 21 of the 33 events here. Each is an all-day entry with a reminder seven days before at 09:00 local time, and a link back to the page that explains it.
Also
Every 2026 US money limit on one pagethe figures behind every deadline here, with sources→ What changed: 2025 vs 2026 vs 2027and what is still not announced→Sources
- www.irs.gov/pub/irs-pdf/f1040es.pdf
- www.irs.gov
- www.ssa.gov/oact/cola/colasummary.html
- www.healthcare.gov/quick-guide/dates-and-deadlines
- www.treasurydirect.gov/savings-bonds/i-bonds/i-bonds-interest-rates
- www.irs.gov/publications/p969
- www.govinfo.gov/content/pkg/FR-2026-01-15/html/2026-00755.htm
- www.irs.gov/pub/irs-drop/n-05-42.pdf
- www.irs.gov/forms-pubs/about-form-1040-es
- www.irs.gov/publications/p509
Information, not advice. Dates are federal and state deadlines differ. A deadline set by your employer’s plan — an FSA spend-by date, a grace period, a claim run-out — is set by your plan document, not by the IRS, so confirm it with your Summary Plan Description or your administrator. Confirm federal dates with the agency that set them.